Brain food

I love smoked oysters but am not too keen on eating those imported from China. Are you aware of anyone who is smoking them locally? T. King

''Another smoked oyster vol-au-vent?'' Those were the fateful last words many 1970s party-goers remember before waking up the next morning with nausea and lingering head pain. Of course, it was the smoked oysters' fault and nothing to do with the gallons of Blue Nun and Ben Ean (white wines popular in Australia at the time) they guzzled. You can buy Aussie smoked oysters direct from Harris Smokehouse in the Adelaide Hills (harrissmokehouse.com.au) from February to July. If you can't wait until then, you can smoke your own. Place opened oysters in the half shell in a bamboo steaming basket. Place several tablespoons of oolong tea leaves in the base of a wok over medium heat. When the leaves are smoking, place the basket over the tea leaves and cover with a wok lid, leaving for three to four minutes. They will be smoky but still raw. Eat immediately. Alternatively, place freshly shucked oyster in the half shell over smoking hardwood chips in the barbecue and cook, lid down, for about 30 minutes, until the oyster is cooked. Eat when the oyster shell is cool enough to handle. They will be salty, smoky and delicious.

Why do mangoes change flavour throughout the season? D. Wilkie

Chris Nathanael, who grows more than 200 different varieties of tropical fruit in his orchard at Bees Creek, near Darwin, says there are a number of reasons. Early in the season, mangoes are harvested before they are tree-ripe, or completely sweet, to be shipped south. If you want the mangoes to sweeten, keep them somewhere warm for a few days, he advises. If mangoes are stored near bananas, the bananas' naturally occurring ethylene will deepen their colour. As soon as the tropical wet season hits the Northern Territory in the next few weeks, their mango season finishes and the production moves to Queensland, where the cycle starts again. Over the Australian mango season, which lasts until March or April, about 10 different varieties come and go, each with different characteristics. Nathanael says ''it has been a bastard of year'' in the NT but he has still managed to produce a decent crop of outstanding mangoes. You can buy a box of 16 to 20 mangoes of different varieties for $68, delivered to your door. Email tropiculture@octa4.net.au. Supplies are limited.

Can I make mayonnaise using the juice from a jar of pickled cucumbers? J. Reynolds

Brilliant question. I love anyone who uses every resource they have in front of them when they are cooking. You need to add acid to the egg yolk before you slowly dribble the oil in to make egg-yolk mayonnaise. I once saw a cook in Spain take the lid off some guindillas - Basque peppers pickled in vinegar plus a nice little dose of E621, known to you and me as MSG - and use some of the liquid. The resulting mayonnaise, doubly delicious with egg, Arbequina olive oil and MSG, was spooned over deep-fried squid and placed in a bread roll for a truly memorable snack. I have made mayonnaise using lemon juice, mustard, tinned beetroot juice, sherry vinegar, blood orange juice, Nanking vinegar and most other comestible acids. I can recommend making a mayonnaise from the juice of pickled ginger finished with some quality sesame-seed oil. Mayonnaise made with raw eggs needs to be refrigerated and used within a few days.

What is the difference between taste and flavour? C. Davies

Some interior designers would argue that everyone is born with flavour but not everyone is born with taste. That, however, is another definition. We taste with our tongues. We taste salty, sweet, sour, bitter and savoury substances with our tongues. With our noses, we smell aromas. Sniffing, we detect smoke, perfumes and the scents of foods. This is called orthonasal smell. When we chew food or swish around wine, we perceive the aromas. This is called retronasal smell. It is only when we combine taste and smell that the two experiences are combined in the brain to create the experience of flavour. So, tongue=taste, nose=smell. Taste+smell in the brain = flavour. To learn more about flavour, consider attending The Science of Taste, a symposium at William Angliss on November 26. See angliss.edu.au/scienceoftaste.